1. Field of the Invention
The present invention relates to the swaging of fittings on lower conductivity tubing and more particularly to swaging of small tubing.
2. Description of Related Art
Present methods include mechanical swaging and standard electromagnetic swaging. In small tubing applications mechanical swaging methods become very hard to implement. The high forces required to swage tend to cause failure of equipment and tooling. Standard electromagnetic swage methods implemented on low conductivity materials require an internal coil and a drive material (copper tubing) which is utilized as a hammer to swage the fitting. Standard coil designs tend to fail where the center conductor turns to wrap around itself. High forces and current levels especially at the corners are the cause of the failure.
In the patent literature, U.S. Pat. No. 3,171,014 issued Feb. 23, 1965 to Ducati teaches that method of forming metal sheet and tubing by electromagnetic technique. Ducati does not address the specific operation and equipment of electromagnetic swaging.
U.S. Pat. No. 3,599,461 issued Aug. 17, 1971 to Aste shows a design for an electromagnetic forming device which utilizes a coil co-designed with other hardware to complete a forming tool not incorporating a likeness to the present swaging coil.